When temporarily parking a car C1 in a crowded city as shown in FIG. 17 outside those cars C previously parked on the road side, it is necessary to give a warning to the other by writing a message such as saying "sorry" or leaving the owner's phone number on a temporary paper which is then adhered on a car window.
However, such a temporary message or reminder sheet may have the following drawbacks:
1. A temporary paper sheet for writing message may be easily missing and lose its warning or message.
2. No illumination is provided for lighting such a temporary paper sheet thereby inhibiting the message at dark or night time.
3. The paper sheet can be used only for a single time and can not be repeatedly used. To dispose a used paper sheet may cause environmental pollution.
The present inventor has found the drawbacks of such a conventional temporary message sheet, and invented the present message board.